Some fluid ejection devices, including, for example, inkjet printheads, have a vertical column of nozzles arranged in a column on a die and defining a swath area. Firing resistors located in a firing chamber below the nozzles are energized, thereby heating fluid in the chamber and causing it to expand and be ejected from the nozzle. Circuitry fabricated on a substrate structure using standard thin film techniques includes a conductive path for carrying electrical power for firing the firing resistors, address signal paths, logic elements, and firing transistors. This circuitry is used to properly energize and operate the firing resistors. Capacitive coupling between the address bus and the fire line or power bus can generate noise and degrade performance.
The cost of a fluid ejection device can be reduced by reducing the device die size. Such reduction, however, may adversely impact the size of power conduits, leading to increased energy variation and reduced print quality. Power conduits may comprise gold which is susceptible to delamination.